1. Technical Field of the Invention
The present invention relates to a process for the production/manufacture of a catalyst useful for the hydrocyanation of ethylenically unsaturated organic compounds.
This invention more especially relates to a process for the production/manufacture of a hydrocyanation catalyst comprising, in particular, nickel values and a water-soluble phosphine.
2. Description of the Prior Art
The hydrocyanation reaction, in particular of organic compounds comprising at least one site of ethylenic unsaturation, is an important industrial reaction permitting the preparation of numerous compounds. Thus, this reaction is employed in the synthesis of organic intermediates, such as 3-pentenenitrile, which is converted into monomers such as aminocapronitrile or hexamethylenediamine.
This reaction is described, in particular, in French Patents No. 1,599,761 and No. 2,338,253 and in U.S. Pat. Nos. 3,655,723, 3,850,973, 3,925,445 and 3,686,264.
This reaction is generally carried out in the presence of a catalyst comprising a transition metal. Such catalysts are also described in the above patents.
Thus, French Patent No. 2,338,253 describes a nickel-based catalyst which is formed by an aqueous solution of a water-soluble phosphine comprising nickel values.
This catalyst is obtained via addition, to an aqueous solution of phosphine, of a nickel compound which is soluble or insoluble in water. The amount of nickel in the aqueous phase then corresponds to that of nickel extracted or complexed by the water-soluble phosphine compound. However, in a preferred embodiment, it is advantageous to employ a nickel compound which is soluble in the phosphine/water mixture. Thus, French Patent No. 2,338,253 specifies that the nickel cyanide compound, which is insoluble in water but soluble in the aqueous solution of phosphine, is a preferred compound in the manufacture of such a catalyst. Other compounds, such as organic complexes or salts of nickel, can advantageously be employed to produce the catalyst.
These various methods for the preparation of a hydrocyanation catalyst exhibit the major disadvantage of requiring a nickel compound which may be either very difficult to manufacture with a sufficient degree of purity, or may have a cost and an availability which adversely affect the economics of the industrial scale operation of the hydrocyanation reaction.